<div class="admin__link-add-btn">
      <%= link_to 'Ajouter un lien', new_link_path, class: "add-link btn btn-outline-success btn-sm article__add-btn" %>
  </div>

  <div class="admin__link-select">
    <%= grouped_collection_select :link, :link_id, Category.order(:name).includes(:links), :links, :name, :id, :name %>
  </div>
  <div class="form_container">
    <%= render 'links/form' %>
  </div>


  <div class="admin__link-manag-btn">
      <%= link_to "Supprimer", link_path(Link.last), class: "btn-delete-custom btn btn-outline-danger btn-sm ", data: {:confirm => "Etes vous sur?"}, method: :delete %>
      <%= link_to "Editer", link_path(Link.last), class: "btn-delete-custom btn btn-outline-primary btn-sm "%>
  </div>

class LinksController < ApplicationController

    def index
      @links = Link.all

    end

      def create
        @link = Link.new(link_params)
        if @link.save
          flash[:notice] = "Sucess"
        else
          flash.now[:alert] = "Error"
        end
        redirect_to root_path
      end
      def new
        @link = Link.new
      end
      def update
        @link.update(link_params)
        redirect_to root_path
      end

      def destroy
        @link = Link.find(params[:id])

        if @link.destroy
          flash[:notice] = "Success"
          redirect_to root_path
        else
          flash[:alert] = "Error"
          redirect_to root_path
        end
      end

    def admin
      @links = Link.all
    end

    private

    def link_params
      params.require(:link).permit(:name, :url, :category_id)
    end

    def find_link
      @link = Link.find(params[:id])
    end
end

<%= simple_form_for(@link = Link.new, remote: true) do |f| %>
  <% if @link.errors.any? %>
    <div id="error_explanation">
      <h2>
        <%= "Errors:" %>
      </h2>
      <ul>
        <% @link.errors.full_messages.each do |msg| %>
          <li>
      <%= msg %>
          </li>
          <% end %>
      </ul>
    </div>
  <% end %>


  <div class="form-group">
    <%= f.input :name, label: "Name", class: "form-control" %>
  </div>
  <div class="form-group">
    <%= f.input :url, label: "Url", class: "form-control" %>
  </div>
  <div class="form-group">
    <%= f.input :category_id, prompt: "- Category -", label: false, collection: Category.order('name') %>
    </div>



    <div class="form-group" data-id='<%=@link.id %>'>
      <%= f.button :submit, @link.new_record? ? "Create" : "Update", class: 'links_add-userlink-button btn btn-outline-primary btn-sm'%>
    </div>

<% end %>